Suspension assembly

Abstract

Hybrid suspension arm assemblies for use in magnetic head/arm assemblies. The suspension arm assemblies utilize plastic components in conjunction with steel to provide excellent damping and rigidity. The hybrid suspension assembly requires much more input amplitude before resonance would become a problem.

What is claimed is: 
     
       1. A suspension arm assembly comprising: (a) a base plate member constructed of a non-metallic composite plastic material;   (b) a spring element joined to said base plate, said spring element being substantially resilient adjacent to said base plate;   (c) a load beam element constructed of a non-metallic composite plastic material, said load beam element being joined at one end to said spring element and having a free end spaced from said one end, said load beam element being substantially rigid along its length to present a loading force at said free end; and   (d) a flexure member fastened to said free end of said load beam element, said fixture including a load protuberance which contacts said load beam.   
     
     
       2. The suspension arm of claim 1 wherein said load protuberance is a ball bearing. 
     
     
       3. The suspension arm of claim 1 wherein said base plate member and said load beam element are connected by a pair of spaced stabilizer bars, said stabilizer bars being constructed and arranged of the same composite plastic and functioning as hinge points across said spring element. 
     
     
       4. The suspension arm assembly of claim 1 further including electrical connection means for providing electrical connections along the length of said assembly between said base plate and said flexure, said electrical connection means including a plurality of electrical conductors encapsulated in an electrically insulating film. 
     
     
       5. The suspension assembly of claim 4 further including head means secured to said flexure, said electrical connection means being in electrical connection to said head means, said electrical means forming a pigtail bend having a twist near the end of the load beam between said flexure to said head. 
     
     
       6. The suspension assembly of claim 5 wherein said pigtail bend region of said electrical connection means comprises a plurality of electrically separate conductive traces secured to a polyimide film base having a thickness of less than about 0.001 inches. 
     
     
       7. The suspension assembly of claim 5 wherein said conductors in said pigtail bend are covered by a top layer of polyimide film having a thickness of less than about 0.001 inches. 
     
     
       8. The suspension assembly of claim 6 wherein the pigtail bend region includes cuts between each conductor running the length of the pigtail bend through the polyimide film and adhesive to provide greater flexibility. 
     
     
       9. The suspension arm assembly of claim 4 wherein said electrical conductors are sandwiched between said base plate and spring, said load beam and spring and said load beam and flexure. 
     
     
       10. The suspension arm assembly of claim 6 wherein each conductor and its insulating base is separated from the other conductors and bases. 
     
     
       11. A suspension arm assembly comprising: (a) a base plate member constructed of a non-metallic composite plastic material;   (b) a spring element being joined at one end to said base plate, said spring element being substantially resilient adjacent to said base plate and including a free end spaced from said one end, said spring element including a flexure at its free end, said flexure including a load protuberance; and   (c) a load beam element constructed of a non-metallic composite plastic material, said load element being joined to said spring element between said flexure and said base plate member, said load beam element being spaced from said base plate member such that said spring element therebetween may function as a spring element, said load beam element cooperating with said spring element where so attached such that the load beam presents a loading force at the free end of said spring element to present a loading force against which said load protuberance may rest.   
     
     
       12. The suspension arm of claim 11 wherein said load protuberance is a ball bearing. 
     
     
       13. The suspension arm of claim 11 wherein said base plate member and said load beam element are connected by a pair of spaced stabilizer bars, said stabilizer bars being constructed and arranged of the same composite plastic and functioning as hinge points across said spring element. 
     
     
       14. The suspension arm assembly of claim 11 further including electrical connection means for providing electrical connections along the length of said assembly between said base plate and said flexure, said electrical connection means including a plurality of electrical conductors encapsulated in an electrically insulating film. 
     
     
       15. The suspension assembly of claim 14 further including head means secured to said flexure, said electrical connection means being in electrical connection to said head means, said electrical means forming a pigtail bend between said flexure to said head. 
     
     
       16. The suspension assembly of claim 15 wherein said pigtail bend region of said electrical connection means comprises a plurality of electrically separate conductive traces secured to a polyimide film base having a thickness of less than about 0.001 inches. 
     
     
       17. The suspension assembly of claim 15 wherein said conductors in said pigtail bend are covered by a top layer of polyimide film having a thickness of less than about 0.001 inches. 
     
     
       18. The suspension of claim 17 wherein the pigtail bend region includes cuts between each conductor running the length of the pigtail bend through the polyimide film and adhesive to provide greater flexibility. 
     
     
       19. The suspension arm assembly of claim 14 wherein said electrical conductors are sandwiched between said spring and said base plate and load beam element.